Paddle-wheel type flow meter

• US 4,936,151 A
• Filed: 06/05/1989
• Issued: 06/26/1990
• Est. Priority Date: 06/03/1988
• Status: Expired due to Fees

• Current Assignee: Tokyo Keiso Kabushiki-Kaisha
• Original Assignee: Tokyo Keiso Kabushiki-Kaisha
• Inventors: Tokio, Sugi
• Primary Examiner(s): Goldstein, Herbert
• Application Number:
  US07/361,498
• Time in Patent Office: 386 Days
• Field of Search: 73/187, 73/861.77, 73/861.87
• US Class Current: 73/861.77
• CPC Class Codes: G01F 1/06 using rotating vanes with tangential admission
• CPC Class Codes: G01F 1/065 with radiation as transfer means to the indicating device, e.g. light transmission

Abstract

In a paddle-wheel type flow meter: a paddle wheel has its paddle tips exposed to a fluid being measured; a light source emits a light to one of a pair of optical-fiber cables which are oppositely disposed from each other through a paddle-wheel housing so as to provide a transmission path of the light across the housing, the transmission path being intermittently blocked off with the paddle tips of the paddle wheel as the paddle wheel is rotatably driven by thge fluid to produce an optical-pulse train directly proportional to the rotational speed of the paddle wheel; the optical-pulse train is translated into an electrical-pulse train through an optical receiver or photoelectric converter connected to the other of the pair of the optical-fiber cables; and the electrical-pulse train is supplied to a suitable digital instrument to determine a flow rate of the fluid, because the flow rate is substantially proportional to a frequency of the electrical-pulse train corresponding to the rotational speed of the paddle wheel.

Claims

1. A paddle-wheel type flow meter comprising:

(a) a boss portion formed in a side area of a fluid-transport pipe, said boss portion being provided with a bore which communicates with the interior of said fluid-transport pipe;

(b) a plug element which is made of transparent materials while detachably inserted in said bore of said boss portion of said fluid-transport pipe;

(c) a paddle wheel is rotatably mounted on a pair of horizontal bearing portions while rotatably driven by a fluid passing through said fluid-transport pipe, said horizontal bearing portions being provided in an inner end area of said plug element, said inner end area of said plug element being exposed to said fluid passing through said fluid-transport pipe;

(d) a pair of insertion holes so provided in an upper surface of said plug element as to substantially vertically extending downward side by side from said upper surface to reach their bottom surfaces which are in the substantially same levels as those of bearings portions of said plug element;

(e) a pair of optical-fiber cables, each of which cables is provided with a pair of terminals, one of which cables forms a light-emitting cable while the other of which cables forms a light-receiving cable, one of said terminals of said light-emitting cable being connected to a light source while the other one of said terminals serves as a light-output terminal inserted into one of said insertion holes of said plug element, one of said terminals of said light-receiving cable being connected to an optical receiver forming a photoelectric converter while the other of said terminals of said light-receiving cable serves as a light input terminal inserted into the other of said insertion holes of said insertion holes of said plug element; and

(f) a pair of optical reflectors, one of which serves as a light-emitting reflector and the other of which optical reflectors serves as a light receiving reflector, said light-emitting reflector being so disposed in a bottom portion of one of said insertion holes of said plug element as to receive a light emitted from said light-emitting cable, said light having been received by said light-emitting reflector being oriented toward a paddle-wheel housing so as to pass across said paddle-wheel housing, said light-receiving reflector being so disposed in a bottom portion of the other one of said insertion holes of said plug element as to receive said light emitted from said light-emitting reflector, said light having been received by said light-receiving reflector being oriented toward said light-receiving cable.

2. The paddle-wheel type flow meter as set forth in claim 1 wherein:

said pair of said optical reflectors are constructed of optical prisms.

3. The paddle wheel type flow meter as set forth in claim 1 wherein:

said pair of said optical reflectors are constructed of optical mirrors obliquely disposed in said bottom portions of said insertion holes of said plug element.

4. A paddle-wheel type flow meter comprising:

(a) a boss portion formed in a side area of a fluid-transport pipe, said boss portion being provided with a bore which communicates with the interior of said fluid-transport pipe;

(b) a plug element which is made of transparent materials while detachably inserted in said bore of said boss portion of said fluid-transport pipe;

(c) a paddle wheel which is rotatably mounted on a pair of horizontal bearing portions while rotatably driven by a fluid passing through said fluid-transport pipe, said horizontal bearing portions being provided in an inner end area of said plug element, said inner end area of said plug element being exposed to said fluid passing through said fluid-transport pipe;

(d) a pair of insertion holes so provided in an upper surface of said plug element as to substantially vertically extending downward side by side from said upper surface to reach their bottom surfaces which are in the substantially same levels as those of beatings portions of said plug element;

(e) a pair of optical-fiber cables, each of which cables is provided with a pair of terminals, one of which cables forms a light emitting cable while the other of which cables forms a light-receiving cable, one of said terminals of said light-emitting cable being connected to a light source while the other one of said terminals serves as a light-output terminal inserted into one of said insertion holes of said plug element, one of said terminals of said light-receiving cable being connected to an optical receiver forming a photoelectric converter while the other of said terminals of said light-receiving cable serves as a light-input terminal inserted into the other of said insertion holes of said plug element;

(f) a pair of optical reflectors, one of which serves as a light-emitting reflector and the other of which optical reflectors serves as a light-receiving reflector, said light emitting reflector being so disposed in a bottom portion of one of said insertion holes of said plug element as to receive a light emitted from said light-emitting cable, said light having been received by said light-emitting reflector being oriented toward a paddle-wheel housing so as to pass across said paddle-wheel housing, said light-receiving reflector being so disposed in a bottom portion of the other one of said insertion holes of said plug element as to receive said light emitted from said light emitting reflector, said light having been received by said light-receiving reflector being oriented toward said light-receiving cable; and

(g) a pair of condensing lenses one of which is interposed between said light-output terminal of said light-emitting cable and said light-emitting reflector, the other one of which condensing lenses is interposed between said light-input terminal of said light-receiving cable and said light-receiving reflector.